介孔碳-氧化硅纳米复合材料的设计合成、结构调控与储锂机制

The development of high-performance, low-cost anode materials for lithium ion batteries (LIBs) is an emerging research frontier in energy storage and nanotechnology. Si-based materials have become the most promising anode material for next-generation LIBs due to their high capacity and abundance. However, their practical application has been hindered by the low conductivity and large volume expansion during lithiation, which lead to poor cycling stability and rate performance. To address the above-mentioned issues, novel mesoporous carbon-silicon oxide nanocomposites (C-SiOx) will be designed. With sub-nanometer-/nanometer-sized SiOx uniformly distributed in highly conductive graphitic/amorphous carbon matrix, the conductivity can be significantly improved; meanwhile, the mesopores can effectively shorten the Li ion diffusion distance and accommodate the volume expansion. Thus, high specific capacity, cycling stability, and rate capability can be achieved simultaneously. Three approaches, including carbon coating, spray-drying, and sol-gel process will be utilized to fabricate the C-SiOx nanocomposites. The fundamental understanding on structure-electrochemical performance correlation generated from this project will advance the application of mesoporous materials in electrochemical energy storage and the development of high-performance anode materials for next-generation LIBs.

高性能、低成本锂离子电池负极材料的研发是新能源技术和纳米技术的交叉和前沿。硅基负极材料具有比容量高、储量丰富等优点，是下一代锂离子电池负极材料的首选；然而其导电性低、嵌锂过程中体积膨胀大，导致其循环稳定性和倍率性能较差。针对以上问题，本项目拟设计一系列介孔碳-氧化硅（C-SiOx）纳米复合材料，通过将纳米级、亚纳米级氧化硅（SiOx）均匀分散在石墨化/无定形碳导电网络来提高其导电性，通过引入介孔来缩短锂离子固相扩散途径和容纳体积膨胀，从而实现比容量、循环稳定性和倍率性能的协同提升。本项目拟采用碳包覆、喷雾干燥、溶胶-凝胶等方法制备C-SiOx纳米复合材料，探索材料制备过程中的结构调控规律，深入研究材料结构与储锂性能之间的内在联系。通过材料、化学、电化学研究的交叉和融合，充分推动介孔材料在电化学储能领域的应用，为下一代高性能锂离子电池负极材料的开发奠定基础。

高性能、低成本锂离子电池负极材料的研发是新能源技术和纳米技术的交叉和前沿。硅基负极材料具有比容量高、储量丰富等优点，是下一代锂离子电池负极材料的首选；然而其导电性低、嵌锂过程中体积膨胀大，导致其循环稳定性和倍率性能较差。针对以上问题，本项目设计了一系列介孔碳-氧化硅（C-SiOx）纳米复合材料，通过将纳米级、亚纳米级氧化硅（SiOx）均匀分散在石墨化/无定形碳导电网络中，提高了其导电性，通过引入介孔来缩短锂离子固相扩散途径和容纳体积膨胀，实现了比容量、循环稳定性和倍率性能的协同提升。采用碳包覆、喷雾干燥、溶胶-凝胶等方法制备了一系列C-SiOx纳米复合材料，制备了一种可逆容量高达 1000 mA h g-1、循环寿命高达 500 次以上的高性能介孔 C-SiOx 纳米复合负极材料，探索了材料制备过程中的结构调控规律，深入研究了材料结构与储锂性能之间的内在联系。通过材料、化学、电化学研究的交叉和融合，充分推动了介孔材料在电化学储能领域的应用，为下一代高性能锂离子电池负极材料的开发奠定基础。